So I scratched my stanchion earlier on my Bomber Z2 and I'm not sure if I should try to fix the stanchion, buy new stanchions, or just upgrade my entire fork. The fork is leaking oil and slowly leaking air. The air is was down a noticeable amount by the end of the ride. Picture:
Hopefully can be fixed with new uppers and new seal kit. Caution: take it apart and make sure the lower leg bushings are still smooth and not damaged. if they are, you may be looking at upgrading the whole fork, or if you want to keep the spring and damper, you will need new lowers in addition to uppers and seal kit.
As your seals dont look particularly wet, there maybe enough life in them to attempt a repair. Done this a few times on motorcycle forks but luckily not needed to try it on an mtb.
Get yourself a very fine file, a sheet of crocus paper and some araldite. Degrease the fork leg and very gently file down the rough edges of the scratches rolling the file around the leg as you slide the file forward. Work slowly and lightly taking care not to start filing the anodising at the side of the scratches. Once all the burrs are cleared off, degrease again and smear araldite over the scratches? Let the araldite set then file off the excess in the same way you cleared the burrs. As you get to the point that the araldite is level with the anodized surface, wrap some crocus paper round the file and finish off the smoothing with the crocus paper continuing to roll the file round the leg as you file. Once your done and the repair feels smooth, clean up the leg and use a toothbrush to clean around the seal. Depressurise the fork and check it slides freely over the repair.
Sounds a faff but it's actually straight forward and just takes a bit of care filing
I too, have done the repair on motorcycle stantions with great success. If you're looking to try a quick fix, you can also try sanding the sharp edges with fine grit sandpaper (something like 1000) and see how that goes.